Prognostic tools for hypertrophic scar formation based on fundamental differences in systemic immunity

Unpredictable hypertrophic scarring (HS) occurs after approximately 35% of all surgical procedures and causes significant physical and psychological complaints. Parallel to the need to understanding the mechanisms underlying HS formation, a prognostic tool is needed. The objective was to determine whether (systemic) immunological differences exist between patients who develop HS and those who develop normotrophic scars (NS) and to assess whether those differences can be used to identify patients prone to developing HS. A prospective cohort study with NS and HS groups in which (a) cytokine release by peripheral blood mononuclear cells (PBMC) and (b) the irritation threshold (IT) after an irritant (sodium lauryl sulphate) patch test was evaluated. Univariate regression analysis of PBMC cytokine secretion showed that low MCP‐1, IL‐8, IL‐18 and IL‐23 levels have a strong correlation with HS (P < .010‐0.004; AUC = 0.790‐0.883). Notably, combinations of two or three cytokines (TNF‐a, MCP‐1 and IL‐23; AUC: 0.942, Nagelkerke R²: 0.727) showed an improved AUC indicating a better correlation with HS than single cytokine analysis. These combination models produce good prognostic results over a broad probability range (sensitivity: 93.8%, specificity 86.7%, accuracy 90,25% between probability 0.3 and 0.7). Furthermore, the HS group had a lower IT than the NS group and an accuracy of 68%. In conclusion, very fundamental immunological differences exist between individuals who develop HS and those who do not, whereas the cytokine assay forms the basis of a predictive prognostic test for HS formation, the less invasive, easily performed irritant skin patch test is more accessible for daily practice.     

Zwei Fälie von Delirium potatorum

Ohne Zusammenfassung     

The influence of the spring activator on the mobility of the lower jaw in traumatically injured patients

For functional rehabilitation and improvement of mandibular mobility, 14 patients with dislocated collum or collum fracture dislocations were treated with a spring activator after surgical-conservative treatment. With an interincisal distance of<12 mm, therapy was started with a loop spring. The average age of the patients was 26.6 years. Eight patients showed additional traumatic injuries, 2 patients were seriously polytraumatically injured. The clinical investigations referring to the maximum mouth opening and maximal interincisal distance resulted in a good to very good functional rehabilitation in all cases. The average maximal interincisal distance of 31.7 mm at the beginning of the spring activator therapy could be increased to 47.3 mm. The largest increase of the maximal interincisal distance was observed after 4 weeks of therapy. The type of reaction, however, differed interindividually. Three patients showed a spontaneous improvement of the interincisal distance within the first 2 to 3 weeks of removal of intermaxillary fixation, whereas 7 patients whowed no improvement or only slightly improved values until insertion of the spring activator. An enlargement of the interincisal distance could be achieved in almost every patient within a relatively short period of time despite a drastically reduced mouth opening. Consequently, because of its mode of action in the form of a neuromuscular influence, the spring activator is especially suitable for the functional rehabilitation of patients with fractures of the condylar process.     

Methods for epidemiologic analyses of multiple exposures: A review and comparative study of maximum-likelihood,preliminary-testing,and empirical-bayes regression

Many epidemiologic investigations are designed to study the effects of multiple exposures. Most of these studies are analysed either by fitting a risk-regression model with all exposures forced in the model, or by using a preliminary-testing algorithm, such as stepwise regression, to produce a smaller model. Research indicates that hierarchical modelling methods can outperform these conventional approaches. I here review these methods and compare two hierarchical methods, empirical-Bayes regression and a variant I call ‘semi-Bayes’ regression, to full-model maximum likelihood and to model reduction by preliminary testing. I then present a simulation study of logistic-regression analysis of weak exposure effects to illustrate the type of accuracy gains one may expect from hierarchical methods. Finally, I compare the performance of the methods in a problem of predicting neonatal mortality rates. Based on the literature to date, I suggest that hierarchical methods should become part of the standard approaches to multiple-exposure studies.     

Chronic obstructive pulmonary disease in Brazilian primary care: Diagnostic competence and case-finding.

AIMS: The developing world is particularly at risk of an increasing health burden due to an increased prevalence of Chronic Obstructive Pulmonary Disease (COPD) secondary to increasing tobacco consumption. However, research is scarce. The objectives of this study were to assess the current competence for diagnosing COPD in primary care in a resource-limited setting in Brazil, and to develop a local patient profile for case-finding. METHODS: 34 general practitioners (GPs) in five areas of northern Brazil recruited adult patients with principal complaints of cough and/or shortness of breath who then had spirometry (n = 142). RESULTS: For the dichotomous variable 'COPD' the degree of agreement between GP diagnosis (n = 64, 18.3%) and spirometric outcome (n = 36, 25.4%) was poor, with Kappa = 0.055 (SE 0.087) and DOR = 1.35. False-positive and false-negative diagnosis proportions were 19.8% and 75%, respectively. Independent risk factors were 'smoking history of more than five pack years' and 'presence of both dyspnoea and cough'. It requires the testing of 2.2 smokers with more than five pack years to detect one patient at risk. CONCLUSIONS: COPD is a common yet underdiagnosed disease in Brazilian primary care. Spirometry improves diagnostic competence and case-finding substantially. If applied in a pre-selected high-risk population, we believe spirometry can be a cost-effective diagnostic tool for case-finding in the resource-limited setting. This study provides important baseline information for effective guideline implementation.     

Intravenous captopril in congestive heart failure

Hemodynamic and neurohumoral effects of intravenous captopril were studied in ten patients with severe chronic congestive heart failure (NYHA Functional Class III and IV). Incremental bolus doses of captopril, titrated to a maximum cumulative dose of 15 mg, were given at 10-minute intervals. Systemic arterial pressure, mean pulmonary capillary wedge pressure, systemic vascular resistance, mean pulmonary artery pressure, and heart rate decreased (P less than .05). Cardiac index and stroke volume index increased (P less than .05). Maximum hemodynamic effects occurred after cumulative doses of 7 mg and were seen within 30 minutes after initiation of therapy; responses persisted for 30-90 minutes after the last dose. Plasma renin activity increased, and plasma atrial natriuretic factor concentration decreased. No adverse effects were observed with the use of intravenous captopril. Thus, intravenous captopril produces rapid and favorable hemodynamic improvement in advanced heart failure patients.